Information retrieval (IR) research has reached apoint where it is appropriate to assess progress andto define a research agenda for the next five to tenyears. This report summarizes a discussion of IRresearch challenges that took place at a recentworkshop.The attendees of the workshop consideredinformation retrieval research in a range of areaschosen to give broad coverage of topic areas thatengage information retrieval researchers. Thoseareas are retrieval models, cross-lingual retrieval,Web search, user modeling, filtering, topic detectionand tracking, classification, summarization, questionanswering, metasearch, distributed retrieval,multimedia retrieval, information extraction, as wellas testbed requirements for future work. Thepotential use of language modeling techniques inthese areas was also discussed.The workshop identified major challenges withineach of those areas. The following are recurringthemes that ran throughout:• User and context sensitive retrieval• Multi-lingual and multi-media issues• Better target tasks• Improved objective evaluations• Substantially more labeled data• Greater variety of data sources• Improved formal modelsContextual retrieval and global information accesswere identified as particularly important long-termchallenges.